An Extremely Brief and Absolutely Condensed History of the Establishment Clause

Throughout the history of the US, the US Supreme Court has interpreted the Establishment Clause in three different ways. Initially it was interpreted as strictly not establishing and religion – unless it was certain branches of Protestantism. This of course totally violates what is colloquially known as separation of church and state. Catholic schools were founded because those parents did not want their children learning Protestant teachings. Beginning in 1971 and after, SCOTUS began to interpret the Establishment Clause through a three part test whose major part was excessive entanglement, including if a law had a secular purpose. In reality, it lead to decisions based, I think, on bookkeeping. Since the presidency of George H. W. Bush, all three branches of government have decided the test is endorsement, meaning that as long as a government entity does not favor one religion over the other, it is constitutional. This of course is impossible - there are an endless number of religions. Hopefully, SCOTUS will eventually get it right.